In conventional tiered anti-arrhythmia therapy, decisions must be made as to when to switch from one tier to another. The timing of such decisions can in some instances be of little consequence; whereas, in other instances, proper timing may act to save a life or prevent excessive myocardial damage. Further, various studies have associated arrhythmia with falls, for example, where an arrhythmia compromises blood flow to the brain or otherwise results in loss of body function (see, e.g., Mills et al., “Cardiac arrhythmia and hip fracture,” Int J Cardiol., 6(3):382–5 (1984)). In the case of a patient fitted with an implanted cardiac therapy device capable of delivering tiered anti-arrhythmia therapy, proper timing of a tier may act to reduce incidence of falls and/or lessen impact of a fall.
Conventional tiered therapy devices generally rely on timers or intracardiac electrograms to determine when to switch between therapy tiers. Hence, such conventional devices do not account for patient position, which may be related conscious state, risk of a fall, etc. As described herein, various exemplary devices, methods and/or systems determine patient position and/or patient movement and optionally use such information to determine when to switch between one tier and another. Various other exemplary devices, methods and/or systems are also disclosed, for example, to aid in detection of arrhythmic conditions.